Boats are normally susceptible to corrosion when out in the aquatic environs. To guard against that, sacrificial anodes are used. How they work is simple; these anodes are attached to the boat and when in the water, they release electrons and corrode in place of your boat. That way your boat would be guarded against deterioration. And that's where the name 'sacrificial' comes from. These anodes sacrifice themselves to save your boat. In the past, you only had one option; zinc. Now they are plenty, and picking the right one is not a piece of cake. The major ones are magnesium, zinc and aluminium. Here's what you need to know before making your choice.
The voltage of these anodes also affects how much sacrificing they'll do. Magnesium has got a higher voltage than zinc, which has a higher voltage than aluminium. The higher the negative voltage, the more willing they are in producing electrons. What this simply means is that a magnesium anode protects your boat more than a zinc anode.
However, a magnesium anode gets depleted faster because it gives off its electrons hastily. Aluminium will get depleted slowest. If you're looking for durability, then aluminium is the best choice.
Cost of the anodes
Once you have an idea of how good the anodes are, you need to take the cost into consideration. Magnesium is the most expensive of the three anodes, followed by zinc and then aluminium. That's why it's not a preferred option for a boating business. You'll be spending too much replacing the anodes. You'll be better off going for zinc or aluminium.
Salt or fresh water boats
The location of your boat is another determining factor on the kind of anode you need. For fresh water, go for alloy anodes such as aluminium as opposed to pure metals like zinc. Mixing aluminium with a metal such as iridium forms an alloy that doesn't form an oxide layer. Zinc, on the other hand, will cause a reaction that creates a protective layer in fresh water. This layer prevents the anode from accomplishing its task.
However, in salty waters, go for less reacting pure metals. Zinc would make a good sacrificial anode, as it reacts less with the compounds in the salty water to form an inhibiting later. Using magnesium in salt water is also a bad idea. It's too reactive and will get depleted before you know it.
For more information, contact a company like Carman Heating.